Report of joint Russian/Norwegian aerial surveys in the Barents Sea in September 2001

The distribution of harp seals in the Barents Sea has been recorded based on incidental sightings from Norwegian and Russian research vessels, Norwegian fishing and coast guard vessels, from Russian aerial surveys (Haug et al. 1994), and from satellite tagged seals (Erling Nordoey, University of Tromsoe, pers. commn.). However, possible overlap in the distribution of harp seals and capelin in early autumn has not been studied. Data on potential harp seal predation on capelin are important in multispecies modelling. Therefore, in September 2001, aerial surveys aimed to study possible overlap between harp seals and capelin were conducted simultaneously with the annual joint Norwegian/Russian acoustic survey of pelagic fish in the Barents Sea. Two Norwegian and two Russian research vessels took part in the survey which covered most of the Barents Se

Distribution and number of marine mammals in the open Barents Sea and their connection with capelin and polar cod distribution [presentation]

This paper presents the data on the character of distribution and the assessment of the number of marine mammals in the open part of the Barents Sea in autumn 2001-2004 by the results from PINRO’s aerial surveys using the airborne laboratory AN-26 “Arktika” and the annual joint Russian-Norwegian vessel ecosystem survey for pelagic fish including capelin and polar cod. The aerial surveys were carried out being combined with the vessel surveys and their tacks coincided or crossed in several points

Preliminary results of the joint Russian-Norwegian airborne research of the Barents Sea in September-October 2002

The conclusions given below are preliminary and will be refined after detailed processing of materials and data gained. 1. Large aggregations of harp seals were observed mostly in the near ice-edge zone, which was north of the distribution of capelin. 2. Aggregations of other marine mammals were recorded in the areas to the south and southeast of the Spitsbergen Archipelago, where data from vessel surveys showed a high biomass of capelin. 3. Data from this survey indicate that there is a relationship between distribution of capelin, and marine mammals and seabirds. Hence, materials and data on distribution of marine mammals and birds acquired during the aerial surveys are consistent with data from vessel-based surveys for capelin and other pelagic fish, and in some cases refine or supplement them. Cooperation and expeditious exchange of data between airborne and vessel surveys are of particular importance when doing aerial research, as it is not always possible to identify a food item in the areas of aggregations of marine mammals and seabirds. Airborne survey allows detecting rather precisely and quickly the potential prey concentrations, primarily capelin that is close to the sea surface, as well as observing marine mammals